This invention relates to improvements in steering column assemblies.
Steering column assemblies for automotive vehicles and the like are increasingly required to be adjustable for rake and, in many cases, reach. This requires the column shroud, within which the steering column is rotatably located, to be fixed to the vehicle by a clamp mechanism which can be locked and unlocked to either prevent movement or permit adjustment of the column shroud position respectively.
One common arrangement uses a column shroud which comprises an inner tubular member and an outer tubular member which telescope one inside the other to permit reach adjustment. A fixing rail welded to one of the tubes is secured to a support bracket by a releasable clamp mechanism. A simple single adjust mechanism includes a generally vertical elongate slot in the support bracket. The clamp mechanism can then move along the slot when in the unlocked position to provide rake adjustment. Reach adjustment can be achieved by providing an elongate slot in the guide rail generally parallel to the axis of the column through which the clamp mechanism passes.
Other mechanisms have been proposed for clamping the tubes to the support bracket.
In one proposed arrangement, the support bracket is generally U-shaped and has two depending arms which embrace the clamp rails, the clamp mechanism passing through respective slots in each arm. One of the arms, or perhaps both, comprise an outer leaf which extends downwards from the base of the U-shaped bracket, and an inner leaf which extends upwards from the free end of the outer leaf towards the base. The clamp mechanism passes cleanly through an opening in the outer leaf and acts upon the inner leaf to clamp the inner leaves, and hence the clamp rails, together. An arrangement of this kind is known from WO 2007/026114A1, the disclosure of which is incorporated herein by reference in entirety.